One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,5)(4,7)(6,8)(9,10,15,13)(11,19,21,16)(12,20,22,17)(14,18,24,23)(1,2,6,8)(3,5,7,4)(9,11)(10,16)(12,18)(13,19)(14,20)(15,21)(17,24)(22,23)(25,26)(27,28)(29,32)(30,33)(31,35)(34,36)(37,38)(39,40)(1,3,6,7)(2,4,8,5)(25,27)(26,31)(28,33)(29,34)(30,35)(32,37)(36,40)(38,39)(1,4,6,5)(2,3,8,7)(9,12,15,22)(10,17,13,20)(11,18,21,23)(14,16,24,19)(25,28,30,31)(26,27,33,35)(29,37,39,36)(32,38,40,34)(1,2)(3,4)(5,7)(6,8)(9,13,15,10)(11,19,21,16)(12,17,22,20)(14,18,24,23)(25,27)(26,28)(29,38)(30,35)(31,33)(32,37)(34,39)(36,40)(1,5,6,4)(2,7,8,3)(9,14,15,24)(10,18,13,23)(11,20,21,17)(12,19,22,16)(25,29,30,39)(26,32,33,40)(27,34,35,38)(28,36,31,37)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.